/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.solr.servlet;

import java.util.ArrayList;
import java.util.List;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.params.CommonParams;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.common.util.ContentStream;
import org.apache.solr.common.util.ContentStreamBase;
import org.apache.solr.core.SolrCore;
import org.apache.solr.request.SolrQueryRequest;
import org.apache.solr.request.SolrRequestHandler;
import org.apache.solr.request.SolrRequestInfo;
import org.apache.solr.response.SolrQueryResponse;

/**
 * DirectSolrConnection provides an interface to Solr that is similar to the HTTP interface, but
 * does not require an HTTP connection.
 *
 * <p>This class is designed to be as simple as possible and allow for more flexibility in how you
 * interface to Solr.
 *
 * @since solr 1.2
 * @deprecated see {@link org.apache.solr.client.solrj.embedded.EmbeddedSolrServer}
 */
@Deprecated
public class DirectSolrConnection {
  protected final SolrCore core;
  protected final SolrRequestParsers parser;

  /** Initialize using an explicit SolrCore */
  public DirectSolrConnection(SolrCore c) {
    core = c;
    parser = new SolrRequestParsers(c.getSolrConfig());
  }

  /**
   * For example:
   *
   * <p>String json = solr.request( "/select?qt=dismax&amp;wt=json&amp;q=...", null ); String xml =
   * solr.request( "/select?qt=dismax&amp;wt=xml&amp;q=...", null ); String xml = solr.request(
   * "/update", "&lt;add&gt;&lt;doc&gt;&lt;field ..." );
   */
  public String request(String pathAndParams, String body) throws Exception {
    String path = null;
    SolrParams params = null;
    int idx = pathAndParams.indexOf('?');
    if (idx > 0) {
      path = pathAndParams.substring(0, idx);
      params = SolrRequestParsers.parseQueryString(pathAndParams.substring(idx + 1));
    } else {
      path = pathAndParams;
      params = SolrParams.of();
    }

    return request(path, params, body);
  }

  public String request(String path, SolrParams params, String body) throws Exception {
    // Extract the handler from the path or params
    SolrRequestHandler handler = core.getRequestHandler(path);
    if (handler == null) {
      if ("/select".equals(path) || "/select/".equalsIgnoreCase(path)) {
        if (params == null) params = SolrParams.of();
        String qt = params.get(CommonParams.QT);
        handler = core.getRequestHandler(qt);
        if (handler == null) {
          throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "unknown handler: " + qt);
        }
      }
    }
    if (handler == null) {
      throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "unknown handler: " + path);
    }

    return request(handler, params, body);
  }

  public String request(SolrRequestHandler handler, SolrParams params, String body)
      throws Exception {
    if (params == null) params = SolrParams.of();

    // Make a stream for the 'body' content
    List<ContentStream> streams = new ArrayList<>(1);
    if (body != null && body.length() > 0) {
      streams.add(new ContentStreamBase.StringStream(body));
    }

    SolrQueryRequest req = null;
    try {
      req = parser.buildRequestFrom(core, params, streams);
      SolrQueryResponse rsp = new SolrQueryResponse();
      SolrRequestInfo.setRequestInfo(new SolrRequestInfo(req, rsp));
      core.execute(handler, req, rsp);
      if (rsp.getException() != null) {
        throw rsp.getException();
      }

      // Now write it out
      return req.getResponseWriter().writeToString(req, rsp);
    } finally {
      if (req != null) {
        req.close();
        SolrRequestInfo.clearRequestInfo();
      }
    }
  }

  /**
   * Use this method to close the underlying SolrCore.
   *
   * @since solr 1.3
   */
  public void close() {
    core.close();
  }
}
